1. Field of the Invention
The present invention relates to a data storage of a construction machine for storing data of detected values and instructed contents of sensors and switches fitted at various positions of a construction machine to observe and control an overhaul time, a service life time, etc. of the construction machine and a data processor of a construction machine for performing data processing such as calculation of an overhaul time on the basis of data stored in the storage.
2. Disclosure of the Related Art
As to a monitoring device for controlling and monitoring an overhaul time and a service life time of the construction machine, a large number of applications, e.g., Japanese Patent Application Laid-Open No. 6-116988, have been filed and already known well.
But, such applications are to achieve monitoring by installing a special sensor and a special monitor in the construction machine. Therefore, a large number of special parts are required, resulting in a high cost.
The present invention was achieved in view of the aforesaid circumstances. And, it is an object of the invention to provide a device which can store data required for monitoring a construction machine without adding a new part to the existing parts already mounted on the construction machine and a device which can make data processing such as calculation of an overhaul time on the basis of data stored.
According to a first aspect of the invention, a data storage device for a construction machine having control means which receives a detection signal of detection means or an instruction signal of instruction means mounted on the construction machine and, on the basis of the received detection signal of the detection means or the received instruction signal of the instruction means, generates and outputs a drive control signal for controlling to drive the construction machine, wherein the data storage device comprises:
operation means which previously determines each level for indicating a content of the detection signal of the detection means or a content of the instruction signal of the instruction means, judges whichever level the detection signal of the detection means or the instruction signal of the instruction means to be input to the control means belongs to at every predetermined sampling time and adds +1 to a count value of the level to which the detection signal or the instruction signal is judged to belong; and
storage means for storing values counted at every level by the operation means.
According to a second aspect of the invention, a data storage device for a construction machine having control means which receives a detection signal of detection means or an instruction signal of instruction means mounted on the construction machine and, on the basis of the received detection signal of the detection means or the received instruction signal of the instruction means, generates and outputs a drive control signal for controlling to drive the construction machine, wherein the data storage device comprises:
operation means which previously determines each level for indicating a content of the detection signal of the detection means or a content of the instruction signal of the instruction means, judges whichever level the detection signal of the detection means or the instruction signal of the instruction means to be input to the control means belongs to at every predetermined sampling time and adds +1 to a count value of the level to which the detection signal or the instruction signal is judged to belong; and
storage means for storing values counted at every level by the operation means; and
data processing means for performing data processing by reading the count values of the respective levels stored in the storage means from the outside.
An embodiment of the first aspect of the invention will be described. In operation section 21 of controller 7, a level indicating a content of a detection signal of individual sensors 9 to 14 or an instruction signal of switch 15 is determined first.
For example, when hydraulic pump 4 has discharge pressure P, as shown in FIG. 5, discharge pressure detection signal P is divided into such levels as P less than 50, 50xe2x89xa6P less than 100, 100xe2x89xa6P less than 150, 150xe2x89xa6P less than 200, 200xe2x89xa6P less than 250, 250xe2x89xa6P less than 300 and 300xe2x89xa6P. The unit of the numerical value is kg/cm2.
It is judged whichever level the detection signal P which is input at every sensor readout interval (sampling time) xcex94t belongs to, and a count value of the level to which the input detection signal P is judged to belong is added for sampling time xcex94t.
For example, it is assumed that the sampling time xcex94t is one second. Then, when the pump discharge pressure signal P of the pressure sensor 10 after a lapse of the sampling time xcex94t of one second from the previous sensor readout time is 200 kg/cm2, the sampling time xcex94t (one second) is added to a time count value of 1119 (seconds) corresponding to the level of 200xe2x89xa6P less than 250 of FIG. 5 to update the time count value to 1200 (seconds) (FIG. 5).
Thus, the time count value is stored in the storage section 22 for each magnitude level of the hydraulic pump discharge pressure signal P as shown in FIG. 5.
According to the second aspect of the invention, the time count value of each level stored in the storage section 22 is read from the outside and subject to data processing. The same processing can be performed by using the respective sensors 9, 11, 12, 13, 14 other than the sensor 10 for detecting the pump discharge pressure P.
Here, the sensors 9, 10, 11, 12, 13, 14 are existing sensors which are mounted as standard on the construction machine in order to control the engine 3 and the hydraulic pump 4. These sensors are generally mounted in order to obtain a feedback signal for controlling when the construction machine is controlled and driven. Therefore, monitoring can be effected by using the existing sensors without newly mounting a sensor for monitoring only, and it is not necessary to add a part. Thus, a cost for configuring the monitoring device can be held low.
The same processing can also be performed by using instruction signals from various switches instead of the detection signals from the sensors. For example, the mode switch 15 is an existing switch which is generally mounted as standard on the construction machine. Therefore, since the existing switch can be used, it is not necessary to add a new part for monitoring only, and a cost for configuring the monitoring device can be held low.
According to a third aspect of the invention, a data storage device for a construction machine having control means which receives a detection signal of detection means or an instruction signal of instruction means mounted on the construction machine and, on the basis of the received detection signal of the detection means or the received instruction signal of the instruction means, generates and outputs a drive control signal for controlling to drive the construction machine, wherein the data storage device comprises:
storage means for storing the detection signal of the detection means or the instruction signal of the instruction means input into the control means in connection with a detection time or an instruction time as data in a past predetermined period of time.
According to a fourth aspect of the invention, a data storage device for a construction machine having control means which receives a detection signal of detection means or an instruction signal of instruction means mounted on the construction machine and, on the basis of the received detection signal of the detection means or the received instruction signal of the instruction means, generates and outputs a drive control signal for controlling to drive the construction machine, wherein the data storage device comprises:
storage means for storing the detection signal of the detection means or the instruction signal of the instruction means input into the control means in connection with a detection time or an instruction time as data in a past predetermined period of time; and
data processing means for performing data processing by reading data for the past predetermined period of time stored in the storage means from the outside.
According to the third aspect of the invention, the detection signals of the respective sensors and the instruction signal of the switch are stored in connection with the detection time and the instruction time for the past predetermined time xcfx84 as shown in FIG. 9 and FIG. 10. Contents of the stored data are updated by the contents of the latest detection signals and the instruction signal at every sampling time xcex94t, and the stored data of the oldest detection signal and instruction signal is erased. Thus, a time change of data for the past predetermined time xcfx84 is always stored.
For example, FIG. 9(a) shows stored data on the pump discharge pressure P for the past predetermined time xcfx84 stored in the storage section 22 by sequentially inputting the detection signal P of the pressure sensor 10. It is seen that the detection signal P is stored in connection with the detection time t.
According to the fourth aspect of the invention, the time series data for the past predetermined time stored in the storage section 22 is read from the outside and subject to data processing.
According to the third and fourth aspects of the invention, the existing sensors and switches mounted as standard on the construction machine are used as they are in the same way as in the first and second aspects of the invention, and it is not necessary to add a new part for monitoring only. Thus, a cost for configuring the monitoring device can be held low.